Elevator operating apparatus



1936. E. a. THURSTON ET AL 2,062,432

ELEVATOR OPERATING APPARATUS 'Filed May 9, 1935 3 Sheets-Sheet l 11M. \IHNIIIIIII llIIIIIIIIIIIIIHIINHHHM 1936' f E. B. THURSTON ET AL. ,432

ELEVATOR OPERATING APPARATUS Filed May 9, 1935 3 Sheets-Sheet 2 fi/mm 03.5mm

1, 9 E. B. THURSTON ET AL. 2,062,432

ELEVATOR OPERATING APPARATUS Filed May 9, 1955 3 Shets-Sheet 3 9 \WNEYS Patented Dec. v1, 1936- UNITED STATES PATENT OFFICE ELEVATOR OPERATING APPARATUS Application May 9, 1935, Serial No. 20,611

20 Claims. .(01. 172-152) This invention relates to elevator operating apparatus of the-general type disclosed in Patent No, 1,943,114 issued January 9, 1934, to John Eaton on a Control system. The main feature of this system is the control of the acceleration and deceleration" of the elevator motor through a device operated'in accordance with the relative movement of the elevator and a speed controlling motorwhich for brevity may be referred was an advance motor.

While this type of apparatus has a number of very desirable features, it was not found commercially practicable until the improvements were made-which are the subject of the present invention. These improvements which render the advantages of the general type of control of practical utility are principally as follows:

First, improvements have been devised whereby the accelerating curve and decelerating curve may be adjusted as desired, independently and without modifying the operation of the advance motor or at any time increasing the speed of that motor over the predetermined speed which com ltrols the desired maximum speed of the elevator.

- {35 A second improvement consists in means whereby the starting of the elevator is made more smooth and at the same time more prompt, number of other improvements being closely connected with this improvement.

A third improvement comprises means whereby the control means is prevented from becoming deranged when for any reason the elevator fails to attain predetermined full speed at the time when it is expected to attain that speed.

.35 Another improvement comprises arrangements whereby the elevator will not respond to a stop cali until the control means has moved a definite dis= tance, whereby the operator can atwill move a short distance away from a landing, in case this becomes necessary. 7

Another improvement consists in arrangements whereby the floor-finding contacts of the apparatus can be quickly and accurately adjusted, without resorting to the cut and try method.

A sixth .improvement is an arrangement whereby the floor-finding and control apparatus can be readjusted to the position of the car even when there has been a slippage equalling substantially a whole floor, merely-by running the elevator to the terminal landing.

Other features relate to safety devices providing for proper operation and preventing improper operation after emergency stops. These comprise features whereby the elevator motor cannot be started after an emergency stop and with thecontrol device in improperposition either by the automatic leveling devices orby closing the starting switch, and also comprises means whereby the control device and the floor-finding apparatus are readjusted automatically to proper position with respect to the car after an emergency stop.

Another improvement consists of a combination of materials for contacts whereby the fioor-finding apparatus will continue to work reliably without renewal over a considerable period of time.

The details of one form of the invention, and other featuresthereof wili appear as the description proceeds.

In the accompanying drawings forming a part of this specification, Figure 1 is a diagrammatic view of the starting and stopping speed control and floor-stop adjustment mechanism employed in this invention; Figs. 2 and 2A together form a wiring diagram showing how the apparatus of Fig. l is connected up in a typical elevator apparatus.

In Fig. 1 there is shown diagrammatically a disc 90, the operation of which affords a rheostat control for starting and stopping the elevator motor, as will be more fuliy'explained later. This disc ii! is mounted'upon a shaft ii driven by a sprocket chain it from a sprocket wheel it mounted upon a sleeve i i of a differen tial housing It, sleeve it being mounted in stationary hearing it. A shaft i'i extends through sleeve it into housing it. At the rightend of housing it, as viewed on Fig. i, there is a sleeve I8 mounted in bearing is and having extending therethrough a shaft 29. Bevel gear ti on the end of shaft ii and bevel gear 22 on the end of shaft 28 mesh with bevel gear 23 on a stub shaft 24 mounted in the differential, housing IS. .A shaft 25 is indicated in alignment with shaft and connected therewith by a coupling 26. Shaft is driven from an advance motor 21 through a reducing gear 28.

. -A sprocket wheel 29 on shaft 20 drives a f om the elevator drive means drives a shaft H through a sprocket wheel 42. So far as the main features of this invention are concerned, shaft 4| might be one with shaft I I but for adjustment purposes, as will be explained later, there is interposed a differential. This comprises a housing 43 having sleeve hubs 44 and 45 mounted in bearings 46 and comprising a bevel gear 41 mounted on a stub shaft 48 in the housing and meshing with bevel gears 49 and 50 on shafts 4| and I1 respectively.

Sleeve hub is driven by suitable means 5| from a reducing gear 52 which is driven at suitable times from a correcting motor 53.

The general operation of this apparatus will be described briefly before going into the details of its connections with the elevator control.

It will be readily understood that through chain 40 shaft 4| is driven at a speed determined by the drive means of the elevator and normally, when correcting motor 53 is not operating, shaft'II is driven at the same speed as shaft 4|, but in the opposite direction.

Assuming that the elevator is at rest and is to .be started, connections are made whereby initial starting power is given the main elevator motor and advance motor 21 is energized. Motor 21 almost immediately attains full speed, whereas the mainelevator motor is started at a comparative slow speed. Consequently, shaft 20 rotates much more rapidly than shaft I1 and as a result differential housing I5 withthe connected sprocket chain I2 and rheostat disc I0 are rotated. The rotation of the rheostat disc, as will be explained later, gradually steps up the power of the main elevator motor until the ele vator attains-a predetermined speed, whereupon, shaft I! will rotate at the same speed as shaft 20, rheostat disc I0 will remain at rest. When commutator cross-head 31 picks up a stop signal for a given floor and vernier disc 33 arrives at the exact position for stopping the elevator, the advance'mo-tor 21 is de-energized and'shaft 20 stops. Thereupon, differential housing I5 is rotated in the opposite direction thereby driving rheostat disc I0 in the direction to de-energize the elevator motor.

As previously indicated, correcting motor 53 is energized when necessary to adjust the automatic starting and stopping devices just described, this correcting motor 53 being for the purpose of adjustment whenever there is creepage or slippage of the elevator cables with respect 'to the driving drum.

Having described thus the general operation of the control apparatus, a specific method of connecting up this apparatus with the usual control means for an elevator in such a way as to accomplish the objects of this invention, as out- 'lined above, and so embody one form of the invention will be. described.

In the diagram shown in Figs. 2 and 2A there are indicated the main power lines 55 and 56.

There are indicated also the .rheostat disc I0, the

advance motor 21, the correcting motor 53, the cross-head 31 and the Vernier disc 33.

The type of drive indicated comprises a main elevator motor armature 51 connected permanently in series with the armature 58 of a generator. A portion 59 of the generator field is included in series with thearmatures and there is also provided a resistance permanently connected inthe-line between the armatures. There 'is also provided a resistance 6| which is at certain times connected in parallel with field portion 59. The generator is provided with the usual main shunt field 62 and the motor is provided with a field 69 permanently connected to the power lines through resistances I0 and II which are shorted at certain times, as will be described later. Thereis also indicated diagrammatically the brake releasing coil I2.

Disc I0 is shown provided with a contact segment I3 which is in contact when the apparatus is at rest, as shown, with contacts 14 and I5 connected permanently to power line 56 through line I6. Normally the segment remains constantly in contact with one or both of these power contacts and supplies current from these power contacts to the other contacts in accordance with the position of the segment. For purposes of illustration it is presumed that segment I3 is moved in the direction of arrow 11 to accelerate the elevator motor for the up direction and is moved in the direction of arrow I8 to accelerate the motor in the down direction. As the. segment moves in the up direction, it will be seen that its end moves concentrically with resistance contacts and successively encounters these contacts, which progressively short out resistance I9. Thereafter, it moves concentrically with contacts 82 of resistance 8|,,encounters contacts 82, thereby shorting out resistance 9| step by step. In the down direction when the segment moves in the. direction of arrow I8 it likewise moves first concentrically with resistance 83 encountering successively contacts 84 and then in the similar manner progressively shorting out resistance 85 by encountering successively contacts 86. Resistance 81 is indicated as common to both the up and down directions, the con- 3 tacts 88 being encountered by segment 13 on the up direction and contacts 89, connected with contacts 88, being by the movement of segment I3 in the down direction.

While the segment is at rest, as shown, it is in contact with two terminals 90 which may be described as limiting contacts, these contacts being permanently connected by ine 9| through relay coil 92 and line 93 to powe line 55 so that coil 92 is energized constantly as long as the segment connects either contact 90 with contact 14 or contact 15. As it moves in the up direction it first encounters a corrective contact 94, while in the down direction it encounters a similar corrective contact 95. As it moves farther in the up or down direction, respectively, it encounters accelerating contaot 96 or 91, respectively, before reaching contacts 80 or 8'4. Immediately above contacts 82 and 86, respectively, there are motor shunt field resistance contacts 98 and 99.

The diagram shows the. various switches in the position which they occupy when the main power switch is open. When the main power switch is closed a number of the relays are ordinarily energized and thus the normal position of a number of switches is changed. The relays and their connectedswitches which are thus normally changed in position by closing the main power line are as follows: coil I00 is energized and closes switch |0| shorting out resistance II of the main elevator motor field. Likewise, relay coil I02 is energized closing switch I03 and thereby energizing coil I04 and closing switch I05 ing of coil-82 closes switch I86 with results which will be described later. Likewise, relay coil I01 I is normally energized closing switch I88 and opening switches I08 and H0, the connection of 8 whichwill be described later. After car switch I14 has been closed, relay coil III is energized closing switches H2, H3, H4, H5, H6, and H1 and opening switch II8. Likewise, the relay coil 303 shown on'Fig. 2A is energized whenever the leveling is operative and opens switch 304.

While the above mentioned relays are normally energized, operating their switches as described, when the main power switch is closed and the car is at rest at a landing with the door closed, various operations result in the opening of the circuits through the various coils. as will be described later. I

Before describing the connections of the various contacts and switches andtheir operation for the various purposes, there will be mentioned first the various relay coils and'the switches operated thereby aside from those already mentioned, beginning at the left side of Fig. 2.- Relay coil I2i when energized closes switch I22 shorting out re= sistance 18 and also closes switches I23 and I24. Likewise, the brake control coil 54 when energized closes switches I25, I28, I21, I28, and I28, and opens switches I38, I3I, I32, I33, and l. Con= nected in the same circuit with the brake coil is a. relay coil I which whenenergized closes a switch-I36 shortingout resistance 60 between the generator and mctorand also closes switch I31 A relay coil. I38; which will be referred to hereafter asthecommon leveling relay, when ener= gized opens switch I38. A field weakening relay coil I, when energized closes switch I42 and opens switch I43. Rheostat safety position relay coil I44 when energized closes switches I45 and I46 while it opens switches I41, I48 and I48. A field relay switch for the up direction 858 when energized closes switches I5I to I51, inclusive, and I I8, while a similar relay coil I58 when ener gized closes corresponding switches 9 to H8, inclusive, for the down direction. The car switch 45 relay .I61 when energized closes switches I68, I69, and I18, while it opens switches Ill and H8. In this connection there may be noted the starting switch us. .There is also indicated at the leit of coil 54 a switch I15 which is indicated diagram maticallyto cover various safety devices such as emergency, overtravel, overspeed, etc. Also ter minal limit switches I18 and Ill are indicated on the diagram at the right of relay coil Mi. At the right of Fig. 2, is indicated also the terminal stop limit switches I18 and I18 and the landing door interlock switch I88. a

' Taking up the portions of the diagram shown in Fig; 2A, there will be described first the switches-and relays in connection with the floorfinding devices;

As previously indicated, the primary floor-find= ing devices are operated in connection with commutator cross-head 31. For'purposes oi illustration, there are shown the connecticnsfor the topand bottom landing and two intermediate landings which may for convenience be called the seventh and tenth floors, respectively. It will be understood that there 'will be similar construc-= 'tions for all other intermediate floors, but for diate floors are, indicated. I

Q .There are "the usual car push buttons of the lock-in type'orits equivalent. The four push buttons I8I to I84, inclusive, being indicated for the landing connections shown. These push but switches ilt'l.

purposes'of simplification only the two interme- I tons connect power line 55 with terminals I to I88, inclusive, which are arranged in a common lane to be encountered in order by a contact I88 on carrier 31,.the numbers being applied from the contact for the top landing downwards in order.

The vernier disc 33 has thereon a contact segment I88 connected to a slip ring I8I contacted by a brush I82. The disc is also provided with another contact segment I83 connected to a slip ring i83 on which brush I85 may ride. A plurality' of contacts I88 are shown. These contacts are connected with contacts I81 arranged in what may be called a vernier lane to be contacted in turn by member I88 mounted on carrier 31. v y

There are also indicated push buttons which are mounted at ,the landings and which also may be of the lock-in type, or as shown, where they operate relays. Only several of these buttons are indicated for illustration purposes. Buttons I88 when pushed in. close connections between power lines 55 and 56 through coils '203 which, when energized, allow switches 2M to close thereby making connec ions through line 282 from power l'ne 53 to contacts 233 in the up landing-button lane. The contacts in this lane are contacted in succession by member 284 mounted upon car= rier $1. i

There are also indicated similar push buttons 285-which are adapted to energize relay coils 286 and thereby allow switches 201 to close and thus connect line 282 to contacts 208 in the down landing push button lane. Contacts 208 are en= countered in succession by contact 208 on carrier ill.

it may be noted that in the up landing push button lane the contact 2W for the top landing is connected permanently with power line 55 as is also the contact 2H for the bottom landing in the down landing push button lane, there being no push button control for the current through these contacts.

There is also shown an reset lane compris ing contacts 282 which are connected to power line 55 through relaycoils 2H3, which, when energized, open switches 1'30. Contact 2N mounted on carrier 3t moves into contact successively with the contacts in the up reset lane.

Similarly in the down reset lane there are contacts 2115 connected to power line 55through relay coils 2i? which, when energized, open A contact 2i? mounted ,oncarrier 37? engages successively the contacts in the down reset lane.

Top contact 2M3 in the up reset lane and contact 2K? in the down reset lane are connected by a line 228 to a limit switch relay coil 216, as will be described later.

Continuing the description of the switches and relay coils from the left to the right of the diagram shownon Fig. 2A, there is a relay coil 22I which, when energized, closes switches 222 to 225, inclusive, and a relay coil 226, when energized, opens a switch 221.

A relay coil 238,301 deceleration purposes, as will be described later, when energized, closes switches 23!, .232 and 233, and opens 234, 235 and 236. The vernier pick up relay coil 231, when energized, closes switches 238, 239 and 280, and opens switch 260. The advance motor relay coil 242, when energized, closes switches 243-and 23 i and opens switch 248. The advance motor relay coil for the up direction 246, when ener gized, closes switches 241 and 248, while the advance motor relay coil 249 for the down direction, when energized, closes switches 250 and I.

The general direction switch operating member 252 is operated in the direction of arrow 253 for the up direction and oppositely for the down direction, being actuated by relay coils 254 or 255, as shown. This device closes switches 256, 251, 258, and 259 against one set of contacts while in the up direction as shown, and the same switches close connection through another set of contacts while in down direction. Operated by the same member 252 there is also a switch 26I permanently connected to power line 56 and making connections with two contacts alternatively in accordance with the position of the member 252. There are also shown on the diagram switches 262 and 263 which are arranged in the hatch way at the top landing and at the bottom landing, respectively, and are closed by a cam on the car when it reaches the respective landing, and close connections from switch 26I to coil 255 or 254, respectively. Connection to the coils from line 56 may be closed at will by reversing push button 305. When coil 254 or 255 is energized, and starts to move member 252, the

' connection is normally broken, but the coils are opens switch 218.

In connection with the advance motor 21, there is indicated a field portion 280 connected in series with a permanent resistance 28I and with resistances 282 and 283, which are controlled respectively by switch 218 for normal running, and by switches 265 or 210 for up or down correcting, as will be explained. There is pro- .vided another field portion 284 for advance motor 21, this being permanently connected with line 55 and through resistance 285 to line 56.

There are also shown resistances 286, 281 and 288 connections to which are controlled in a manner which will be disclosed later.

The leveling apparatus comprises a low speed leveling switch 290 which may be closed by a cam 29I at each landing and an up leveling switch 292 and a down leveling switch 293 which may be closed in proper sequence by a cam 294 at each landing. Relay coil 295 connected to line 56 through up direction leveling switch 292, when energized, closes switches 296, 291 and opens switch 298. Relay coil 299, connected to power line 56 through down leveling switch 293, when energized, closes switches 300 and 30I and opens switch 302. The low speed .relay coil 303 which may be connected through switch 290 to line 56 when energized, opens switch 304.

There are also shown car push buttons 305 for reversing the direction of the elevator when desired.

Having indicated the various relay coils and switches operated thereby somewhat in the order of their occurrence on the diagram so as to facilitate the location of the various relay coils and switches hereinafter referred to somewhat in accordance with the number applied thereto, the general operation of the device will be described and the connections of the various relays and switches entering into that operation will be pointed out where such operation is of importance in connection with the present invention.

When the attendant closes starting switch I14, this closes a circuit from power line 56 through a normally closed switch I41 and relay coil I61 and-through car gate contact switch 320 and the regular safety devices I15 to power line 55.

The operation of relay coil I61closes a circuit from line 56 through the switch I69 and a line 32I to directional switch 256, and from thence I The leveling relay coils 295, 299 and 303 may -be connected to line 56 as previously indicated.

From the other end of these coils a line 325 leads to normally closed switch I08 and thence through switches I1 I, I49 and I I2 to power line 55.

The operation of relay coil I50 closes switch I 52 and so connects line 55 to the generator shunt field 62 and also closes switch I5I and connects the field to line 56 through resistances. These resistances, however, comprise all of the resistances 64 to 68, inclusive, resistance 63 being shorted by' line 326 through switch 304 to line 56. This results in operation of the elevator motor at a speed slightly above the low leveling speed (say approximately 50 F. P. M.).

The energizing of relay coil 54 connects the brake coil 12 and switch coil I35 to line 56 through switch I25 and to line 55 through switch I26. It also closes switch I21 and by-passes the normally closed switch I48 so the coils I50 and 54 will remain energized when switch I48 is opened. The normally closed switch I 30 also opens the supply to relay coil I01.

Relay coil I01 is of the time-drop-out type so, when its coil circuit is opened, it may lag from one-half to one second before it opens. The opening of this relay closes the switch I09 which completes a circuit from line 56 through switch H4 and to line 322 through switch I53. This by-passes switch I69 and supplies current to coil I50 and allows it to hold in when relay coil I61 is de-energized, and thus forms a holding circuit.

The de-energizing oi relay coil I01 also closes a switch IIO which connects line 55 with switch I31 closed by coil I35, and this completes the circuit to switch I I5 closed by coil I I I and thence through line 326 to switch 236 and then line 321 to switch I06 and back through line 328 and through coils 242 and 246 and line 329 to switch I54, thence to switch I68 and so to line 56. Switch 243 closed by the energizing of coil 242 by-passes switch I68, so that coils 242 and 246 remain energized after coil I61 is de-energized.

The energizing of relay coils 242 and 246 closes a circuit from line 56 through series field 280 of advance motor 21, through resistance 29I. switch 218, switch I, switch 241, the armature of motor 21, switch 248, switch 244, line 330, and switch I26 to line 55. This immediately starts advance motor 21 at full speed, which starts at 'full speed disc 33 and carrier 31. Disc I is started in the clock-wise direction at full speed, less the low speed of the elevator efiected as described above. a

As the segment 13 engages contact 98, it will energize relay coil I44. The operation of this relay closes a circuit from line 56 through switches I45 and I I9 to the generator shunt field resistance 65 and shorts out the section 64 of the resistance.

The effect of this is to cause the generator to lows coils I50 and 54 to be energized, is by-passed vator.

increasing the elevator speed. Further movement of disc I0 engages successive contacts 80, shorting out successive lengths of resistance 19 and thereby gradually increasing the elevator speed. Further movement engages the first contact 82 and places resistance 8I in parallel with resistance 66, and successive engagement with other contacts 82 shorts out successive portions of resistance 8|, thereby further speeding up the ele- Engagementof segment 13 with contact 98 closes a circuit to relay coil I, the operation of which opens switch I43 and de-energizes relay 'coil I00, thus inserting resistance H in shunt field 69 of the elevator motor, and thus causing further increase of the elevator speed.

Further movement of segment 13 engages the first contact 88 andgthrough this and switch I42 connects resistance 81 in parallel with resistance '81. When this point is reached this should be suflicient to cause the elevator to operate at its rated full speed, or the speed set by the advance motor 21. When this is the case, the disc I0 will not move further and the elevator will operate at full speed.

Assume an up call is registered at the tenth floor landing button I83, with this being the case, the

up tenth landing lock type relay 200 has been tripped so its switch 20I is closed when contact 204 of carrier 31 engages the tenth floor contact 203in the up landing button lane, it closes a circuit from line 55 through switch 20I, and to direction switch 258, thence through switch 221 to relay coil HI and through line 33'I andswitch I28 to line 58. Switch 223 closed by energized coil 22I connects line 55 to coil 22I, thereby bypassing the circuit to coil 22I from line 55 described above. Switch 224 closed by energizing coil 22I connects line 55 to the relay coil 228 which is permanently connected to line 56, and thus .opens switch 221 in the line between coil HI and switch 258.

The closing of switch 225 by energized coil 22I connects line 58 through switch 258 tocontactthrough switch 238 continues.

2 I4 on carrier 31 and through the up tenth landing relay reset coil M3 to line 55. This opens switch 20I so no following car can pick up the same floor call. Also, switch 222 closed by coil 22I closes a circuit from line 55 to contacts I83 and I98 on carrier 31, and through contact I81 to the corresponding contact I98 and thence through switch 251, relay coil 231, line- 332 and switch I46 to line 56.

The energizing of coil 231 closes switch 238' and connects the resistances 286, 281 and 288 in parallel with the armature of advance motor 21,

and the opening of switch 24I puts in series with the advance motor armature a resistance 282. The efiect of doing this is to dynamically slow down the advance motor 21. The closing 01 switch 238 connects the sideoi coil 231 that was supplied from disc 33 to the supply of coil 242. The closing of switch 240 connects from line 58 through "relay coil 230 to line 55..

The energizing of coil 230 opens'switch 238 that supplied the original energy to coil 242, but this makes no immediate difference while the supply When switches 234 and 235 are closed, they by-pass portions of resistances 68 and 61, but the opening or these switches does not immediately have any eflect because these resistances are already shorted by the operating of segment 13.

The closing'of switch 233 by-passes switch 240 that caused coil 230 to be energized. This circuit is from line 56 through line 338, switch 233, line 339, switch I29 and line 340 to coil 230.

Since the energizing of relay coil 231 causes a slowing down of the advance motor 21, it also causes a slowing down of disc 33. The length oi! segment I80 on disc 33 is just long enough for this slowing down action to be completed.

Since the supply now for relay coils 242 and 248 is coming through contact I36 for the tenth floor,.as soon as the segment moves oi! oi! this contact these relays will be tie-energized and thereby stop the advance motor. Since the elevator is still traveling at practically full speed and the .advance motor is stopped, the differential construction causes disc I0 to be rotated counterclock-wise at practically full speed. This-rotation towards this original position moves segment 13 out of engagement with the'various contacts in the inverse order of their engagement vdescribed above, and thereby increases the resistance in the generator shunt field, causing a slow down of the elevator, and as the car arrives at the tenth floor the disc III will have returned to its neutral position, as shown in the diagram.

To insure that a car will continue, or floor find, to the floor at a speed higher than the leveling speed, even though the relay coil I44 may have been de-energized by the segment 13 moving oil of contact 36, a second circuit is provided through the normally closed switches 302 and 238 and a normally open switch 232, through lines 3 to switch II8. These serve to short out the resistances 63 and 84 and will give a car speed of say 90 F. P. M.

Since the car has approached the floor landing so that leveling switch 232 is closed, relay coil 285 is energized. This closes switch 238 and switch 238 opens the by pass around resistance 64. This causes reduction in car speed to the high leveling of say about 50 F. P. M. I

The energizing of coil I2I closes switch I22 and shorts out resistance 10 in the elevator motor shunt field. This helps to slow the elevator down and also strengthens its torque for leveling. Coil I2I closes switch I23 and completes a circuit through resistance 324. This is used as a time protection, so that the attempt to level will cease after a predetermined time in case something has happened so leveling does not take place nor-- mally The closing of switch I24 closes a circuit through relay coil I01. The energizing of coil I01 opens a switch I09 that is in the holding cir cuit around switch I 89 so the leveling can now take control of the elevator.

The energizing of relay coil I38 opens switch I39 in circuit with time relay coil I02, and after a definite time will open switch I03 in the circuit to switch coil I04. This opens switch I05 in the shunt resistance 6|, which is connected around the series field 59 of the generator. The opening of this shunt circuit increases the effect of the series field for leveling.

As the elevator continues toward the floor levcling the switch 290 engages the cam 29I and energizes relay coil 303. The energizing of this coil opens switch 304 so that resistance 83 in the generator shunt field circuit is no longer bypassed. This causes a further decrease in elevator speed to say 20 F. P. M., and is used for the final stopping when the switch 292 leaves cam 290.

Of course, when switch 292 opens, it de-energizes coil 295 and this results in de-energizing coilsI50, 54, I38 and I2I. This brings the elevator to a stop. It will be understood that should the car have traveled a distance sufiicient to close switch 293, it would in the regular manner move the car back to the floor at the low leveling speed by energizing coils 299-, I58, 54, I38 and I2I. It should be noted that de-energizing of coil 54 opens switch I29 in the by-pass circuit to coil 230, so when once opened it remains open.

If in the previous illustration button I82 in the car had been pressed instead of the button at the landing, the operation would have been the same except that the tenth up landing relay would not have been operated; and the circuit would have been closed by an engagement of contacts I89 and I89 instead of by the engagement of contacts I91 and I98. The car push button may be locked in by either electrical or mechanical means.

While the circuits have been followed through for only a stop at one floor, it is believed that the operation of the apparatus under normal circumstances will be fairly clear from this description without specifically pointing out the action when the car is operated to different floors or in the down direction. It may be pointed out that when the car is operated in the down direction the direction switch 252 is moved by the energizing of coil 255 so as to swing the attached switches to the difierent connections shown. In such an operation coil 249 is energized instead of coil 246 so as to rotate the advance motor 21 in the opposite direction. Also coil I58 is energized instead of coil I50 so as to operate the elevator motor in the opposite direction, and segment 13 is moved in the anti-clockwise direction during acceleration engaging successively contacts 95, 91, 84, 88, 99 and 89 instead of the corresponding contacts 94, 96, 80, 82, 98 and 88, as hitherto described.

A particular feature of the operation thus far described which constitutes a part of the present invention consists in the method employed of accelerating and decelerating at desired rates without interfering with the regular operation of advance motor 21. When the operation of the elevator is being accelerated, it is generally desired to cut out some of the resistance more rapidly than it is desired to insert this resistance during deceleration. In the patent heretofore referred to, which constitutes the nearest prior art of which applicants are aware, the relatively rapid acceleration is obtained by speeding up the advance motor more rapidly during this time than for its regular operation. This is highly objectionable since it makes possible a failure to properly slow down the advance motor when full speed of the elevator is reached and under such circumstances the elevator would acquire excessive speed in its attempt to equal the speed of the advance motor. This disadvantage is avoided very simply in the above construction by the arrangement which by-passes a certain portion of the resistance in the shunt field of the generator when the advance motor is energized. This has been pointed out in the foregoing description in connection with the energizing of coils 242 and 246 so as to close the regular circuits through advance motor 21. It has also been pointed out that the resistances are reinserted when these coils are de-energized. At the same time coil 230 is energized closing the shunt circuits around portions of resistances 88 and 61. It will be understood that as many of these shunt circuits may be provided as desired, and they may be located as desired in connection with the resistances so as to produce the desired accelerating curve. It will be readily understood that the same results might be obtained with many variations in the details of the circuits employed, the diagram indicating merely one way in which this can be accomplished. An important principle is that a desired amount of resistance is shorted out while the advance motor is energized so that the ac-v celeration of the elevator motor will be produced at the desired rate, and when the advance motor is de-energized so that the deceleration of the elevator will begin, at the same'time the shorting r of these portions of resistance is opened so that the resistances are reinserted successively in thedecelerating steps as they occur in proper order. It will be understood ,that both the amount of the resistances thus shorted out during acceleration and reinserted during deceleration as well as their location may be adjusted as desired so that the acceleration and deceleration may be independently adjusted to the proper rate without in any way changing the'regular speed of the advance motor. I

Another improved feature of the present invention relates to the order of operations in starting the elevator. In order to start the elevator it is necessary to release the brake and start the elevator motor, advance motor 21'being energized also to provide for proper acceleration of the main motor. By the connections shown, the closing of the starting switch at once energizes coils 54 and I50 or I58, thus releasing the brake and making connections for starting the motor in the selected direction at slow speed. Advance motor 21 is not energized until relay coil I01 is de-energized and drops out, closing switches I09 and H0 after a delay of V second or so, as described above; This results in a smoother acceleration and at the same time more prompt release of the brake and start of the elevator than would result from the energizing of the advance motor before giving the brake time to release and before energizing relay coil I50 or I58;

' Another feature is the provision of means for stopping the turning of disc ill at the desired point even though the elevator should not reach its intended speed, and without stopping the oper-. ation of the elevator. In the'connections shown, this is provided for by the arrangement whereby the excessive rotation of disc l0 moves'segment 13 out of engagement with contact 93 and thus break the circuit through coil 32. This opens switch I06, and stops the advance motor 21. The continued movement of the car brings segment i3 back into engagement and restarts the advance motor. This action may be repeated as often as necessary until the car picks up the intended speed or until it reaches its destination, where it may be stopped and the difficulty may be remedi'ed, if due to anything more than a temporary condition, such as overloading. In any case, the

- failure of the car to reach predetermined speed does not prevent its reaching its intendeddestination ,or involve any other difficulty aside from its somewhat slower travel. Another improvement is the provision whereby the-car may be started away from a floor even if a button for that landing is being held closed. Switch H6 is in the circuit 332 of coil 231, and

- is closed only when segment 13 engages contact of this differential modifies the relation between 36 or 91 and energizes coil I. Accordingly, coil 231 is not energized and-a stop button for the floor is not effective until. the car has moved far enough from a landing to engage segment 13 with contact 96 or 91, at which time the floor stop'contacts and disc 33 and carrier 31 will not ,be in register for that floor. This prevents interference with starting'the car by either landing buttons or car buttons for that floon The operation of the elevator under normal conditions having been described, there will now be described the initial adjustment of the contacts in connection with the floor-finding appa-. ratus, and then there will be described automatic means for subsequent adjustments; or readjustment of various parts as required because of ordinary slippage or creeping of the cables, and also adjustments-and safety devices employed in connection with emergency stops and other unusual or accidental conditions.

In the regular operation of the apparatus, vernier disc 33 and carrier 31 are connected to the elevator mechanism'only through a differential,

and the advance motor 21 operating one member the elevator and the vernier control. Accordingly, the onlyway to set the contacts engaged by movement of disc 33 and carrier 31 is by the cut and try method, in the absence of some spe- -cial'provision. Such an operation in a tall build- The .car is then moved in succession to the diflocated properly with respect to the contacts on carrier 31, and likewise contacts J36 are located ferent floors and the contacts in the various lanes,

If the cables slip or creep with respect to the Q driving drum. the floor-finding apparatus including disc 33 and carrier 31 are thrown out of adjustment with respect'to the elevator car. The next time the car is stopped, advance motor 21 is stopped with carrier 31 and vernier 33 in register with the contacts for that floor. 'Thereafter, disc it is moved by the movement of the ment of contacts by carrier 31 and disc 33 stopped advance motor 21 too soon or too late, movement of the carlevel with the floor will result in turning segment 13'short of -or past its neutral position, so that it will engage contact 94 or 35. With 'drive drum, until the car is leveled. If engagethe brake set and switch "I31 closed, this ener- 4 gizes correcting motor 53, through the. appropriate series held 345 or m to turn' or. drive it in the direction to move segment 13 back to neutral position through the two differentials.

Thereafter, the iloor-flndlngdevice will operate H apparatus at any stop where it is out of adjust-- ment a small amount.

However, under extreme conditions, it may be finder becomes approximately a full floor or more out of adjustment. The provision for automatic correction of this condition merely by running the car to a terminal landing is another feature of the present invention.

For illustration, suppose that through slippage the car -is a full floor or more below the position it should be in relation to carrier 31. Moving the car upward results in engaging contact 204 and terminal contact 2M, and the car stops at the next floor, which will be a door or more below the top. However, the operator can close the switch i1l, thereby energizing coils and 34, and start the motor upwards at low speed. The advance motor will notoperate, as the limit relay coil 214 continues to be energized by the circuit from contacts Ill, Ill, 233 andfl. The car will continue to move, therefore, at slow speed. Since advance motor 21 remains stationary. the turning of shaft ll tends to turn housing '40 possible for the cable toisl-lp so far thatthe floor.-

i3 and to drive disc 10 in counter clockwise direction; but as soon as segment 13 engages 'contact 35, correction motor 33 is energized, and in this way disc 10 is kept from turning during the travel of the car to the top landing. whereupon it will be seen that the floor-finding apparatus will be in proper relation to the car. It may be pointedout that motor 33 may be energised when the brake is released through line 341 and switch 213 held closed by coil 214.

A similar correction may be made where the slippage was in the opposite direction by running the car downward until contact 2" ensues contact 2I I, and then continuing downward at slow speed to the bottom landing.

When an emergency stop is made, as by opening a circuit by any of the usual emergency stop safety devices, diagrammatically indicated by switch I15, the car may stop at a position near enough to a landing so that when the safety device is reclosed, the leveling apparatus might be brought into play by the closing of switch 292 or 293. It would be very undesirable to have the leveling apparatus operated under such conditions and, therefore, the emergency devices are arranged, as indicated in the diagram, to open the circuit through relay coil III. With'this coil cut out the leveling devices are inoperative and the holding circuit being broken also the leveling device cannot be rendered operative until car switch I14 has been closed. This safety feature is another phase of the present invention.

When an emergency stop is made the car is stopped ordinarily much more quickly than under normal deceleration. Accordingly, the car is brought to a halt before segment I3 has returned to normal position and frequently it may still engage contact 96 or 91 which is operated to energize relay coil I44. While relay coil I44 remains energized and holds switch I41 open, it

will be seen that closing starting switch I14 is not effective. This is another valuable safety factor introduced by the present invention. If the connections were such that the elevator could be started by closing starting switch I14 under the conditions indicated, some of the resistance might be shorted out and this might result in starting the car'too quickly resulting in overspeeding which might trip various emergency safety devices and lead to.trouble in this way. By preventing the starting of the elevator when the segment I3 is not in approximately normal position, this difficulty is overcome.

Another feature of the present invention is the arrangement of connections so that after an emergencystop, while either leveling or starting the car by switch I14 is prevented in the manner described above with segment 13 in abnormal position, there-is provided automatic means for returning it, to proper position. If this were done by correcting motor 53, it is obvious that it would leave the floor-finding devices out of adjustment with respect to the car. For example, if the emergency devices stopped the car in ten (10) feet instead of twenty (20) feet, which may be indicated for purposes of illustration for the usual stopping distance, segment I3 would be only half returned to normal position and at the same time the floor-finding devices, that is carrier 37 and disc 33, would be approx'mately ten (10) feet out of proper registry with the car. Returning the segment 13 to its normal position by correcting motor 53 would leave the car and floor-finding devices in the same relative position. However, it will be seen that while coil I II is deenergizcd by the interruption of the circuit therethrough by the opening of emergency switch I15, switches I I6 and I I1 are opened so that correcting motor 53 cannot be energized. Asindi-. cated above, the closing of switch I14 will not energize coil I61 when the segment I3 is materially out of normal stopping position and, therefore, coil III cannot be re-energized even if emergency switch I15 is again closed. However, de-energizing of coil III which results in the opening of switches H6 and II! also results in the closing of switch IIB whereby a line I40 leading through coils 264 and 2" is connected to the power line 55 and by line 149 or 0, respectively, to contact 94 or 95. The energizing of coil 264 or 269 starts advance motor 21 and brings segment 13 back to normal position until it disengages the respective contact 94 or 95, and at the same time operates disc 33 and carrier 3'! and returns the floor-finding apparatus to the same position with respect to the car that it would have had if the stopping had been in the normal manner. This is a quite important feature of the present invention as it avoids a great deal of difficulty after an emergency stop.

' It will be seen that by the connections as described, the various stated objects of this invention are effected. It will be readily understood that the various objects might be accomplished by different connections which might be worked out by one skilled in the art with the aid of the foregoing disclosure.

Another improvement which has been an important item in making a commercially practicable device of the type described herein relates to the material employed in the contacts. While it is recognized that any suitable materials might be used for the various contacts, it may be pointed out thatsomewhat unusual conditions are encountered with respect to certain contacts in connection with the devices described herein, and that these somewhat unusual conditions are overcome by using material particularly selected for pro- ,ducing the desired results and so far 'as applicants are aware the fact that these materials would produce the particular results has not been previously known and, accordingly, is a discovery by the present applicants. 4

In testing out an apparatus constructed along the lines of the present invention, it was discovered that the rapid movements of segments I90 and I93 on disc 33 resulted in excessive wear so that ordinary copper contacts would not stand up for a satisfactory length of time. After much experimentation, it was found that copper or similar conducting material could be coated with a thin layer of chromium and the increased resistance of the chromium did not seriously interfere with the operation of the device, while it prolonged the life of the contacts very greatly.

The stationary contacts I96 also wear to some extent but with the contacts I90 and I9! being chromium plated, it was found that copper contacts could be employed for contacts I98.

Where copper contacts are employed, there is always danger of oxidation suflicient to interfere with the passage of current. In the construction shown, this is not troublesome with contacts tacts I96 has operated quite satisfactorily. Thevarious contacts on carrier 31 are also subjected to considerable wear and it has been found quite helpful to provide these with a chromium plating. However, the stationary contacts in the various lanes which are engaged by the contacts on carrier 31 are not subjected to sumcient wear to prevent troublesome formation of oxide thereon when the stationary contacts are made of copper. Therefore, for these stationary contacts which are subjected to relatively little wear, it has been found preferable to employ silver.

The chromium plating of the moving contacts upon disc 33 and carrier II with the stationary contacts associated with disc 83 being of copper and the stationary contacts in the various lanes associated with carrier 3lbeing of silver has been found a verysatisfactory and practical arrangement, eliminating the dimculties otherwise encountered under the somewhat unusual conditions to which these contacts are subjected.

There are a number of lines that run from connections shown on Fig. 2 to connections shown on Fig. 2A and that have not been specifically referred to in the foregoing description. It is believed that the operation of these lines is sufficiently clear so that detailed description is unnecessary, but in order to avoid any-confusion because of the necessary division of the diagram into two figures, these lines not previously mentioned and running from one figure to the other are given I reference numbers for purposes of shown. It will be readily understojodthat any other type of leveling equipment might be substituted, and that in general the old and standard features of the equipment might be varied and their substantial equivalents employed, and

that specific equipment and connections are indicated by way of illustration, there being many other available specific embodiments of the features and combinations constituting the essentials of this invention and set forth in the appended claims.

What'I claim is:

1. A control system for elevators and the like, comprising a main electric driving motor for the elevator, resistance determining the speed of said main motor, an auxiliary motor, a control device for cutting in or ,out portions of said resistance, means positioning said control device in accordancewith the relative speeds of said motors, and means cutting out ,portions of said resistance during the entire time while the auxiliary motor is energized and cutting it in when the auxiliary motor is de-energized.

2. A control system for elevators and the like, comprising a main electric driving motor, resistance determining thespeed. of said motor, an auxiliary motor, a control device varying in accordance with its position the amount of said resistance in the motor control circuit, a diiferential having one member driven from the main motor, one driven by the auxiliary motor, and one positioning the control device, and means automatically subjecting a greater amount of resistance to the control of said control device when the auxiliary motor is de-energized than ance in the said control circuit when the control device is in its stopping position and the auxiliary motor is de-energized than when the control device is in the same position and the auxiliary motor is energized.

4. A control system for elevators and the like, comprising a main electric driving motor, resistance determining the speed of said motor, an auxiliary motor, a control device varying in accordance with its position the amount of resistance in the motor control circuit, a diiierential having one member driven from the main motor, one driven by the auxiliary motor, and one positioning the control device, a given movement of said control device controlling a different amount of resistance when the auxiliary motor is energized from that which it controls when the auxiliary motor is de-energized.

5. A control system for elevators and the like, comprising a main electric driving motor, resistance determining the speed of said motor, an

auxiliary motor, a control device varying in accordance with its position the amount of the resistance in the motor control circuit, a differential having one member driven from the main motor, one driven by the auxiliary motor, and one positioning the control device, a given movement of said control devicecontrolling a different percentage of the resistance when the auxiliary motor'is energized from that which it controls when the auxiliary motor is de-energized.

6. A control system for elevators and the like, comprising a main electric driving motor, resistance determining the speed of said motor, an auxiliary motor, a control device varying in accordance with its position the amount of resistance in the motor control circuit, a differential having one member driven from the main motor, one driven by the auxiliary motor, and one positioning the control device, a given movement of said control device controlling a different amount of resistance when the main motor is started from that .which it controls when the main motor is stopped.

'7. An electric motor system comprising a main motor, manually operable means for starting the main motor, an auxiliary motor, means controlled by the auxiliary motor for accelerating the main motor in accordance with the speed attained by said main motor, and means automatically starting the auxiliary motor upon the energization-of the'main motor.

8. A control system for elevators and the like, comprising a main electric driving motor, an electrically controlled brake for the elevator, an auxiliary motor, control means for said main motor, difierential driving connections between said motors and said control means, manually operable means for energizing said main motor at low speed and releasing said brake, and automatic means timed to start said auxiliary motor when said brake is released.

9. A control system for elevators and the like, comprising a main electric driving motor, an electrically controlled brake for the elevator, an auxiliary motor, control means for said main motor, differential driving connections between said motors and said control means, manually operable means for initiating the energizing of said motors, means in connection with said auxiliary motor for de-energizing it and thereby de-energizing the mainmotor, and means preventing the restarting of said motors by said manual means with said control means in improper position.

10. A control system for elevators and the like, comprising a main electric driving motor, control iliary motor, diflerential driving connections be-' tween the motors and said control means, manually operable means for initiating the energizing of said motors, automatically operable means for stopping said motors with the elevator in preselected position, emergency stop means, and means rendering said manually operable means inoperative while said control means is out oi its normal stopping position.

11. A control system for elevators and the like, comprising a main electric driving motor, control means having a normal stopping, position J and operable in one direction from and to said normal position to accelerate and decelerate the main motor in the up direction and in the opposite direction from and toits neutral position to accelerate and decelerate the main motor in the down direction, an auxiliary motor, diii'erential driving connections between the motors and said control means,-manually operable means for initiating the energizing or said motors, automatically operable means for stopping said motors with the elevator in pre-selected position, emergency stop means, and means rendering said manually operable means inoperative while said control means is at either side of its normal 80 stoppingp ition.

12. A control system for elevators and the like, comprlsing a main electric driving motor, control means having a normal stopping position and operable from and to said normal position as to accelerate and decelerate the main motor, an

auxiliary motor, diilerential driving connections between the motors and said control means, and automatic means, actuated by excessive movement of said control means away from its nor-,

(a ma] stopping position, to cut oil power from said motor. 18. A control system for elevators and the like, comprising a main electric driving'motor. control means having a normal stopping P tion,

and operable in one direction from and to said normal position to accelerate and decelerate the mainmotorintheupdirectionandintheop-, posite direction from and to itsneutral position to accelerate and decelerate the main' motor in the down direction, an auxiliary motor, diirerential driving connections between the motors and said control means, and automatic means, actuated by excessive movement of said control means in either direction away from itsnormal' Itoppingposition,toeutoi!poweri'romsaidauxiliary motor. I

14. A control system for elevators andthe like,

.' comprisingamainelectrlcdrivingmotoneom -trol means having a normal stopping position andoperableinonedirectloniromandtosaid normal-position to accelerate and decelerate the main motor in direction and in'the o'pposits direction (remand to its neutral position toaccelerate anddecelerate the main motor in u the down direction, an auxiliary motor, diiier- .ential driving connections between themotors and said controLmeans, and automatic means, actuated byexce-ive movement or saidcontrol. meansineitherdirectionawaytromits normal Mppins position. to de-energiae said auxiliary motoronlywhilesaidcontrol'deviceremainsin 'its'extreme position.

' llxAaegitroi system for a device movable in a constrained pith, comprising a maindriving motor !or said device, control means ior said locked, whereby said contacts may be adjusted in accordance with the position of the movable is member of the selector when said device isat the selected point in its constrained path.

16. A control system for elevators and the like, comprising a main electric driving motor for. the elevator, a control device for the main motor, so an auxiliary motor, diilerential driving connections between said motors and the controldevice, a stop selector means'driven by the auxiliary motor, and 'means preventing the stop se-' lector from being elective for stopping-the ele- 88 vator' until the'selector has moved a pre-determined distance away from its normal stopping position. v U l 17. A control system for elevators and the libs, comprising a main electric for the 80 elevator, a control device for the main motor having a normal stopping position, an auxiliary motor, diil'erential driving connections between said motors and the control device, stop selector means driven by the auxiliary motor, means automat i- 86 'cally stopping.. the auxiliary motor, and,returning the control device to its normal stopping position when the stop selector reaches its. position appropriate for stopping, at a terminal stop or the elevator, and manually controlled means for ener- 40 gizing the main motor at slow speed and moving the elevator on to its appropriate position at said terminal landing without changing the position of said control device or stop selector, after said selector has reached its said position prematurely. 45

m position when the elevator stops'normallyso emergency stop' means adapted to stop said elevator more quickly than-it normally stops after operation of the stop selector, and automatic means for energizing said auxiliary motor and turning said control device to its normal stopping posi- 60 tion "and the stop selector to its corresponding position atter an emergency stop has been made.

19. A control system iorelevators and the libs,

comprising a main electric driving motor for the gency stop means adapted to stop said elevator more quickly than its normal stopping, automatic leveling means-adapted to level the car with the selected floor after it has been decelerated by said stop selector, and means rendering the leveling devices inoperative after an emergency stop while said control device is out of its normal stopping position.

20. A control device for elevators and the like, comprising a main electric driving motor, re-

slstance determining the speed of said motor, an

auxiliary motor, a control device having a stopping position and varying in accordance with its position the amount 01' said resistance in the control circuit, means operating the control device in response to the relative speeds of the two said motors, means to start the main motor, automatic means operable upon the energizing of the main motor to energize the auxiliary motor, and means cutting out a portion of said resistance, with the control device in stopping position, when said auxiliary motor is energized. 

